The lifetime model of turn-to-turn insulation in inverter-fed motors is studied. A lifetime model has been built by considering the effect of inverter-generated high voltage rise rate (dv/dt up to 20 V/ns). This model is followed by the generalised probabilistic model, in which the lifetime is proportional to the nth power of the voltage rise rate. Moreover, by investigating the effect of voltage rise

Trace hydrogen sulphide (H2S) could reflect the severity of insulation faults in gas-insulated switchgear (GIS), therefore, accurate and fast detection of low-concentration H2S is important for on-line monitoring, fault diagnosis, and state evaluation in GIS. Ag-Ti3C2Tx chemiresistive-type sensors were fabricated via drop-coating with self-reduction synthesised Ag-doped Ti3C2Tx. The as-prepared sensors

This issue of IEEE Vehicular Technology Magazine includes 10 open-call articles addressing nonterrestrial networks (NTNs), artificial intelligence/machine learning (AI/ML) for millimeter-wave (mm-wave) wireless communications, the convergence of the metaverse and mobility systems, free-space optical (FSO) vehicle-to-everything (V2X) communications, maneuver coordination for cooperative driving and

This time of year is special for the IEEE Vehicular Technology Society (VTS). We will recognize this year’s VTS Award recipients at the 98th Annual IEEE Vehicular Technology Conference held in Hong Kong (VTC2023-Fall). We will also bring together engineers, researchers, and other professionals at the 2023 IEEE Vehicle Power and Propulsion Conference (VPPC) to be held in Milan, Italy. I hope we will

As the world anticipates the arrival of 6G networks, the spotlight is increasingly turning toward innovative technologies that can push the boundaries of wireless connectivity even further. Among these transformative technologies, Reconfigurable Intelligent Surfaces (RIS) have emerged as a promising solution that holds immense potential to revolutionize wireless communication in the 6G era.

Reports on public rail transportation projects that are being developed and launched around the world.

Research on the next generation of cellular technology, called 6G , is ramping up rapidly all over the world. Now is the time to influence what should be in and what should be out under the 6G umbrella. The European Union (EU) has earmarked €900 million (∼US$974 million) for research and innovation for 6G spread over seven years (2021–2028), and the EU is expecting the industry to invest the same amount

Ice monitoring methods were applied for 110 kV and above transmission lines with tangent towers. However, the change in the vertical span is not considered, and a significant difference lies in the tower-conductor structure of 10 kV transmission lines. For this reason, a proposal is made about the ice monitoring method for the 10 kV transmission line with tangent tower in alpine landform, which includes

The laboratory lightning test is essential for assessing the effectiveness of lightning strike protection (LSP). Particularly, direct lightning strike damage can be performed with pulsed current injection into the specimen. This paper focuses on the dynamic process of arc plasma and shock wave behaviour in the vicinity of the ‘strike’ point. A rod-plate discharge load is built for testing aluminium

As voltage measuring devices are widely used in the high voltage power system with a primary-secondary-fusion structure, electronic voltage transformers are directly connected to the primary conductor and would face much more serious electromagnetic environments than general secondary equipment. As a result, they would still experience failures even when general protection measures are adopted to suppress

The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball lightning. However, crucial aspects concerning the plasma components of the resulting afterglow remain unresolved. Notably, the measurement of the electron density, a critical parameter, has not been fully achieved thus far. In this study, microwave diagnostics and video recording were employed during

Ester liquids (ELs), as the alternative transformer liquids to the conventional mineral oils (MOs), have been increasingly used in power transformers with high voltage ratings. Among various properties, the lightning impulse breakdown voltages (LIBDVs) have been studied elaborately in the past 2 decades under different electric field uniformities. The electric field uniformities do have an effect on

Accurate assessment of hot-spot temperature is essential for the safe operation of power transformers. Existing dynamic thermal models cannot estimate hot-spot temperature accurately since some input parameters are roughly determined by transformer capacity and cooling mode while ignoring the effect of winding structure, tank dimensions, and material physical properties. To improve the accuracy of

Rubber-based composites based on ethylene propylene diene monomer (EPDM) with excellent non-linear electrical conductivity are preferred to serve as reinforced insulation in cable accessories, which can self-adaptively regulate electric field distribution and avoid electric field concentration due to the non-linear conductivity. The conductive carbon nanotubes (CNT) are filled into EPDM to improve

Basin-type insulator often has small cracks due to stress concentration. The current method cannot accurately reflect the stress condition of the insulator to find the stress concentration areas. To solve these problems, a method for detecting two-dimensional plane stress (δ1 and δ2) within different depth ranges in a basin-type insulator is proposed based on critically refracted longitudinal (LCR)

Vibration with a frequency of 100 Hz is widely distributed in the power equipment, and it can provide a new way to supply energy for sensors by vibration energy harvesting. The vibration energy harvesting method based on electromagnetic induction principle was studied through the arrayed structure of magnets and coils. Static magnetic field models were established for four magnet array structures and

Computational screening of single gases to replace SF6 for electrical insulation has been challenged by the difficulty in combining various mutually exclusive properties especially for dielectric performance with liquefaction and environmental properties. To reveal the inherent correlations between dielectric strength (Er), boiling point (Tb), and global warming potential (GWP) of dielectric materials

Silicone elastomers are widely used to encapsulate power electronic devices. However, such devices may be subjected to square-wave pulsed voltages with a high rate of change, which can create significant challenges for encapsulation insulation. In this article, the molecular vibration of silicon elastomer at the edge of pulsed electric field is studied. Firstly, the relationship between the intensity

Oil-paper insulation material is an essential component for oil-filled transformers, and polyimide (PI) insulation paper is a novel material in the field of electricity. The improvement of insulation class for insulation paper has gained significant attention in recent years. In this study, SiO2 nanoparticles were modified with a silane coupling agent (KH550), and the KH550-SiO2 was added to the fibre

A key factor limiting the development of silicone rubber insulating materials is their short service life in harsh operating environments. The establishment of a self-healing system is desired to improve the long-term operational performance of silicone rubber and effectively extend its service life. In this study, poly(urea-formaldehyde) microcapsules containing polydimethylsiloxane healing agents

Sulphur hexafluoride (SF6) decomposed products analysis is highly critical in the early-stage fault diagnosis of gas-insulated switchgear (GIS). Spectrum technology outperforms traditional methods on non-invasiveness, no sample preparation, and no consumption. Here, the authors present an improved fibre-enhanced Raman spectroscopy (FERS) as a comprehensive analytical tool to detect a suite of SF6 decomposed

The surface charge accumulation on the basin insulator is a particular problem in high-voltage direct current (HVDC) gas insulated switchgears (GIS) and gas insulated transmission lines (GIL), which restricts the development and application of extra/ultra high-voltage (EHV/UHV) technology. The surface charge distribution and anti-flashover performance are closely related to the insulator shape. To

To enhance the DC electrical performance of cross-linked polyethylene (XLPE), the graftable antioxidant methacrylic acid 2-hydroxy-3-(4-anilinoanilino) propyl ester (GA), which contains carbonyl and amino groups, and the crosslinking coagent trimethylolpropane trimethacrylate (TMPTMA), which contains carbonyl groups, are individually or co-grafted onto XLPE. The slightly higher deep trap density introduced

In an offshore wind farm, a high-voltage switchgear interruption in an offshore substation creates a high-frequency, high-amplitude overvoltage that can cause severe electromagnetic interference problems in the intelligent electronic device. To address this issue, mathematical models, vector fitting and finite element method were used to build an integrated electromagnetic disturbance conduction model

Silicone rubber (SR) is widely used for cable insulation and operates in multi-stress coupling conditions. Its dielectric properties and ageing performance are the essential factors affecting cable operation. In this study, the frequency domain spectroscopy of unaged SR and SR aged under various conditions is measured. The dielectric responses before and after ageing are analysed in depth by the conjoint

Owing to advanced power electronic and electrical applications developing towards miniaturisation and integration, the thickness-dependent DC breakdown mechanism of epoxy/multiwall-carbon-nanotube nanocomposites is under investigation. The results indicate that the breakdown strength of nanocomposites containing 0.05 wt% multiwall-carbon-nanotubes rises by ∼18%, and the breakdown strength falls exponentially

The ionic transport process is an important counterpart to charge transport in oil-paper insulation, and it significantly impacts oil flow electrification at the oil-paper interface. Despite this, the dynamics of this phenomenon and the underlying mechanisms remain unclear, particularly at the molecular level. To understand this fundamental aspect, we conduct Molecular Dynamics study on the transport

Recently, high-performance inverters are widely adopted in many applications such as photovoltaic (PV) systems, plasma generation, medical imaging, wireless power transfer, electric vehicle, and so on. For these applications, small volume, high power density, and fast response characteristics are greatly expected, to achieve this goal, improving the operating frequency is the fundamental approach.

Fibre-reinforced polymer (FRP)/rigid polyurethane foam (RPUF) interface is susceptible to moisture intrusion in addition to natural ageing during operation. This study investigated the influence of moisture intrusion on the FRP/RPUF interface under natural ageing using experiments and molecular dynamics (MD) simulations. Water absorption, shear strength, and leakage current tests were used to clarify

A current-voltage composite controller for an arc suppression inverter is designed. The current and voltage at the fault point are reduced by injecting current and regulating the neutral point voltage to completely eliminate the risk of fire and overvoltage caused by a single-line-to-ground fault arc. A cascaded inverter is used, and the effects of the ground parameter measurement, line impedance voltage

The flashover strength of epoxy (EP) insulations in the High voltage direct current applications of future energy grids can be improved by tailoring their surface condition. This work aims to improve the DC surface flashover characteristics of EP after being treated with sandpaper of different gradings. Samples with virgin EP and homogenously modified EP considering varying surface roughness (Ra = 0

Maintenance tasks in distribution networks are often accompanied by hazards associated with high altitudes and high voltages. By utilising robots instead of human operators to perform these tasks, potential risks can be avoided, while productivity can be increased. This research proposes an intelligent power distribution live-line operation robot (PDLOR) system based on a stereo camera to replace human

Displacement susceptibility is a very important parameter to characterise the displacement polarisation of dielectrics. Two methods based on the time-domain current and potential combined spectra are proposed to measure the displacement susceptibility. One is based on the time-domain polarisation current and decay potential combined spectra, and the other is based on the time-domain depolarisation

Connected automated vehicles (CAVs) can use vehicle-to-everything (V2X) communications to exchange their driving intentions and coordinate their maneuvers. Message generation rules are necessary to decide when and how maneuver coordination messages (MCMs) should be generated. The design of these generation rules must consider the critical nature of maneuver coordination and the limited bandwidth available

In recent years, electrified mobility (e-mobility), especially connected and autonomous electric vehicles (CAEVs), has been gaining momentum along with the rapid development of emerging technologies such as artificial intelligence (AI) and Internet of Things. The social benefits of CAEVs are manifested in the form of safer transportation, lower energy consumption, and reduced congestion and emissions

Recently, the applications of cold atmospheric plasma (CAP) in liquid treatment have attracted increasing attention owing to its excellent medical efficacy. It has been proved that CAP can effectively enhance the biological activity of vegetable oils due to the generation of reactive species. Optimising the reactor parameter is an important approach to regulate reactive species in plasma-activated

The high-altitude platform station (HAPS) concept has recently received notable attention from both industry and academia to support future wireless networks. A HAPS can be equipped with fifth-generation (5G) and beyond technologies such as massive multiple-input multiple-output (MIMO) and reconfigurable intelligent surface (RIS). Hence, it is expected that HAPS will support numerous applications in

Variation in air pressure severely affects the insulation of electric vehicle (EV) motors, hence weakening the reliability of EVs for safe operation. Nomex-polyimide-Nomex, a typical insulation material for EV motors, was used to investigate the motor insulation performance under different air pressures. The results show that the partial discharge inception voltage is significantly reduced for EV motors

High temperature vulcanised silicone rubber (SR) has excellent hydrophobicity and thus is widely applied both in indoor and outdoor insulation. According to the analysis of different experimental ageing tests and field investigation of SR, temperature and humidity are considered to be the fundamental factors during degradation. Hygrothermal ageing was proposed in this study to simulate the chalking

Spark is a widely studied plasma source for active species production; however, it experiences unstable transitions (e.g. to a thermal arc) at high frequencies or long pulse durations. In this study, the sparks generated in a pulse train were studied and modulated based on a physics-corrected deep learning method. Our results show that a highly repeatable and stable spark plasma source can be achieved

An insulator surface charge may be responsible for flashover along the insulator surface. In this study, experimental investigations of post insulator surface charge are performed using a variety of voltage, gas type, and gas pressure conditions. Combining the model of surface charge transport, the dominant charge transition is revealed considering gas partial discharge. The results show that hetero-polar

Electric vehicles (EVs) are one important enabler for the evolution of sustainable transportation sector. However, one major barrier to the widespread adoption of EVs is their limited battery capacity and the excessive time required to fully charge depleted batteries. Although techniques such as charging with a rapid charger and battery swapping may partially alleviate such concerns, the corresponding

The water desalination plants are important infrastructures in the integrated electrical-water system. Currently it lacks accurate and time-efficient model for these plants, which affects the optimality of the integrated electrical-water system operation. This letter proposes an algebraic model to calculate the electricity consumption of the freshwater production efficiently. Results of case study

Based on a modal approach, this letter identifies the primary cause for the ill-conditioning of a Power Flow Problem (PFP) and proposes a method to circumvent this numerical weakness. The technique consists in modifying the ill-conditioned PFP Jacobian matrix for the standard Newton method initial iterate by moving away just its smallest magnitude eigenvalue from near zero. The state deviations for

This letter presents the idea of ranking critical prosumers in using a novel state-sensitivity function (SSF). The SSF is designed to work in a given nodal power injection hypercube, and thus the proposed ranking method captures the effect of injection subspace. An element-wise maximum Jacobian is obtained, that quantifies the worst-case sensitivity of each injection on each state. Results from various

The impact-increment technique is introduced to speed up the reliability assessment of hybrid AC/DC distribution systems (hybrid AC/DC DSs). Based on that conception, two criteria are developed to determine independent contingency states, whose impact-increments are always 0 and can be eliminated. Criterion I is based on total loss of continuity (TLOC), which can identify the minimum granularity subsets

This letter addresses the parameters design problem for converter-based virtual synchronous generators (VSGs), which is crucial for stable operation. Existing methods only consider performance optimization based on the small-signal model or qualitative analysis of large-signal stability. However, it remains to be elucidated on how to quantitatively design virtual inertia and damping to ensure transient

This work proposes an application of dynamic average consensus in interlinking converters of AC/DC microgrids with a distributed anti-windup for dealing with steady-state errors from communication delays. The proposed controller consists of a PI control that looks after the power-sharing between interlinking converters while achieving a global incremental cost consensus. The controller uses an observer

Residential ON/OFF devices, such as thermal-controlled loads and smart appliances, have great potential for providing frequency regulation service in the power grid. These devices can be engaged using centralized, distributed, or local control. However, both centralized and distributed controls require significant costs for communication infrastructure, while local controllers may perform poorly due

The Linearized distribution flow (LinDistFlow) model has been widely utilized in distribution network optimization and control. However, its dense formulation hinders its applications, especially in distributed power flow computation and optimization. This letter reveals the implicit sparsity embedded in the LinDistFlow model, which is corresponding with the radial network topology. It naturally enables

As the wind turbine height increases, the probability of multiple upward leaders flashes within the wind farm increases. In this study, an upward lightning flash containing 21 upward positive leaders (UPLs) initiated from different wind turbines in Zhangbei Wind Farm was analysed. The average speed of the UPLs was 1.2 × 105 m/s, which mostly decreased to zero before reaching the cloud height. Only

Variable frequency industrial drives are tuned to start from a standstill. However, in most of industrial applications, IM may spin due to external force offered by wind, load, etc. Apart from this, due to short power interrupts, the drive may trip, and bringing the motor to a standstill may require several hours due to its high inertia. In these scenarios, restarting the IM may draw a huge inrush

The switching operation of gas insulated switchgear (GIS) disconnector will produce multiple random spark discharges between the gas gaps of the disconnector. Each spark discharge can be affected by various random factors, such as trapped charge on the load side, the initial operating phase, gap distance and operating speed of the disconnector, leading to dispersion characteristics. At present, some

The direct bonding copper (DBC) substrates of insulated gate bipolar transistor (IGBT) modules degrade inevitably under cycling thermo-mechanical stress, causing potential threat to the reliability of IGBT modules. However, little attention has been paid to monitoring their degradation. This paper proposes a DBC degradation monitoring method for IGBT modules, which combines boundary-dependent thermal

Excessively high temperatures inside a power transformer can accelerate the ageing rate and even cause unplanned outages. Accurately estimating the hot-spot temperature (HST) of a power transformer is important for regulating the load and ensuring long-term operation. In this study, a closed-loop model of a 110-kV product transformer with an oil natural/air forced (ONAF) cooling mode is built to predict

The current reliability criterion (RC) of the film capacitor (FC) is usually a fixed value, which does not consider the staged capacitance loss caused by moisture diffusion under high temperature and/or high humidity. The expected lifetime of capacitors would deviate far from the actual one. The moisture diffusion process of the encapsulated FC is analysed based on Fick's second law. In order to investigate

Surface flashover is a devastating electronic avalanche along the gas–solid interface when a high electric field is applied, which is a potential issue that threatens the safe operations of advanced power electronic, electrical, and spacecraft applications. However, the underlying physical mechanisms for surface flashover development are still under investigation owing to the complex charge transport

Natural ester insulating oil is widely used in transformers due to its good fire resistance and biodegradability. It is mainly composed of triglycerides, and there are some differences in fatty acid composition and content among natural esters. Therefore, the fault diagnosis methods based on dissolved gas analysis are different. Three kinds of natural ester insulating oils are used to study the dissolved

Air gap impulse discharge characteristics of railway tunnel-catenary at high-altitude are of great significance to the electrical insulation design. The existing altitude correction methods for non-uniform air gaps are not applicable to tunnel-catenary. To investigate the impulse discharge characteristics of the tunnel-catenary, a typical structural model was built in an artificial climate chamber

As the current Editor-in-Chief (EiC) of IEEE Journal of Emerging and Selected Topics in Power Electronics (JESTPE), I would like to express my gratitude to our exceptional editorial team, which includes the founding EiC, Dr. Don Tan, the immediate past EiC, Dr. Joseph Olorunfemi Ojo, our deputy EiCs (DEiCs), editors, and associate editors (AEs). I would also like to acknowledge the invaluable contributions